Neurosurgeon and presidential candidate Ben Carson is asked about his endorsement of dubious Mannatech supplement company

Presidential candidate Ben Carson was asked during debate this week about his ties to Mannatech, maker of a dubious nutrition supplement based on "glycoscience."

Carson responded:

I didn�t have an involvement with them. That is total propaganda, and this is what happens in our society. Total propaganda. I did a couple of speeches for them, I do speeches for other people.

Jim Geraghty, who thoroughly covered these ties already last January in the National Review, yesterday pointed out that Carson's response appears to be untrue, or in Geraghty's words, "bald-faced lies." Geraghty explains how the paid speeches were compensated highly enough that reasonable people will recognize this as a paid sponsorship arrangement.

Indeed, that point becomes obvious with even a brief look at Carson's video about Mannatech, in which he praises the company for "trying to find a way to restore the natural diet as a medicine, as a mechanism for maintaining health." Carson says:

The wonderful thing about a company like Mannatech is that they recognize that when God made us, he gave us the right fuel, and that fuel was the right kind of healthy food.

Geraghty describes the company's "long, checkered past" in the National Review.